The changes induced by long-term alcohol ingestion in brains of mice and rats will be determined. The effects will be ascertained in animals with and without the development of physical dependence and also following alcohol withdrawal. The capacity to synthesize proteins under both in vitro and in vivo conditions will be assessed with special attention to the properties of ribosomes and the components of the cell sap and ribonuclease activity. The capacity to synthesize proteins in different brain regions and cell types will also be studied. RNA metabolism will deal with labeling profile achieved in the nuclear and cytoplasmic RNA following the administration of a radioactive RNA precursor. The half-lives of messenger, transfer and ribosomal RNA will be measured and the activity of RNA polymerase will be determined. Additional investigations will be undertaken on proteins of purified neural membranes. This will include a determination of their composition and biogenesis and a study of their distribution and conformation utilizing biochemical and biophysical approaches. BIBLIOGRAPHIC REFERENCES: Smith R.C., Parker, E.S., and Noble, E.P., Alcohol and affect in dyadic social interaction. Psychosomat. Med., 37:25, 1975. Fleming, E.W., Tewari, S., and Noble, E.P., Effects of chronic ethanol ingestion on brain aminoacyl-tRNA synthetases and tRNA. J. Neurochem. 24:553, 1975. Tewari, S., Fleming, E.W., and Noble, E.P., Alterations in brain RNA metabolism following chronic ethanol ingestion. J. Neurochem. 24:561, 1975.